1. Field of the Invention
The present invention relates to floor maintenance machines and more particularly relates to a new improved construction of a pad-holding device for units used with floor maintenance machines, such as for buffing, cleaning, polishing and like maintenance-type operations.
2. Description of the Background Art
Floor maintenance machines commonly employ a rotating annular pad for floor buffing, cleaning and polishing. With such machines, the weight of the apparatus generally rests on the pad, the pad being driven by a vertically oriented rotating drive shaft.
Coupling devices for connecting polishing pads to floor maintenance machines commonly include a circular flange on the vertical motor-driven shaft of the machine, the flange having a coaxial projection extending below the flange and being provided with radial projecting lugs spaced below the flange. A second part of the coupling typically includes an annular plate member for receiving the coaxial projection so as to move into engagement with the flange. Extending radially outwardly from the central opening of the plate member are recesses which permit lugs to pass through the plate member so that when the plate member is turned relative to the flange, the lugs move behind a rear face of the plate member to thereby prevent axial movement of the plate member relative to the flange. To limit the turning of the plate member relative to the flange, the plate member usually has solid ramps cast on the rear face, so that the lugs slide up the ramps until the lugs jam tight against the ramps as the annular plate is brought into tight engagement with the flange. Alternatively, the plate member is provided with downwardly projecting stops and pressure springs to limit turning of the plate member relative to the flange. The annular plate member forming the second part of the coupling is generally fixedly connected to the rotating pad member, e.g., by a plurality of screws. Typical coupling devices are described in U.S. Pat. Nos. 3,600,735 and 4,391,548.
When the annular plate member of a coupling device is fixedly attached to a pad member as by a plurality of screws, replacement of the pad requires time-consuming removal of the screws or the necessity of having on hand additional pad members to which have previously been attached the annular plate members of the coupling device.
There remains a need in the art for a device allowing quick interchangeability of pads without decoupling a coupling device.